Ignition apparatus



Oct. 30, 1934. c DAVIS, JR 1,978,696

IGNITION APPARATUS Filed Nov. 25, 1931 Patented Oct. 30, 1934 IGNITION APPARATUS Charles Hall Davis, Jr., Anderson, Ind., assignor,

by mesne assignments, to General Motors Corporation, Detroit, Mich, a corporation of Delaware Application November 25, 1931, Serial No. 577,253

1 Claim.

: motive vehicle type.

An object or" the present invention is to provide a distributor head that is neat and compact in arrangement, and that is of particular value in connection with the standard type of ignition mechanism for use on engines having a large number of cylinders; and to provide a construction which shall be simple in design and economical to manufacture and operate in an efficient manner. This is accomplished by providing a distributor head having a plurality of parallel spark plug wire terminals each having a post portion within the head, the posts extending alternately into planes spaced a substantial distance apart, a rotor provided with as many conductors as there are planes, and means for conducting sparking impulses to the rotor conductors.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing wherein a preferred embodiment of one form of the present invention is clearly shown.

In the drawing:

Fi ure 1 a plan view of a distributor head embodying the present invention;

Figure 2 is a bottom plan view of the distributor head;

Figure 3 is a sectional view on the line 3-3 of Figure 1; and

{sparks per cylinder for an eight cylinder engine and is, therefore, provided with two circular rows of eight terminal sockets 21 and 22, each having terminals 23, the upper end of which is provided with a pointed portion 24 and the lower end of which provides a part or post 25. The

sockets 21 form an inner circle and the sockets 22 form the outer circle.

The distributor head 20 is made of molded insulating material, such as bakelite or the like.

' This head is provided with an annular skirt having a series or set of eight inwardly extending bosses or ribs 32. These ribs are spaced equally on the inner surface of the skirt 30 of the head 20, and a second series or set of eight inwardly extending ribs 33 is spaced equally within the head above the first group. The second group of ribs 33 extends nearer to the axis of the head. Each lug or rib 32 and 33 is provided with a flat portion 34 and 35 respectively, through which the posts 25 protrude. The flat portions are so arranged with respect to each other to form an inverted step formation or, in other words, the ribs 32 and 33 extend alternately in their respective positions within the head in a separate plane and at a substantial distance apart to prevent short circuits and to provide a neat and compact distributor head. This head is provided with a closed end 36 having an annular ring conductor or annular ring 37 embedded therein. The conductor is connected to a high tension terminal 38. The termial 38 is provided with a pointed end 39 to receive a spark plug wire, the end being located within a socket 40 formed on the outer surface of the head 20. A central boss 41 extending from the closed end 36 toward the open end of the head insulatingly supports a high tension terminal 43 having a spring pressed button 44 associated with its inner end. The outer end of the terminal 43 is provided with a pointed end 45 extending into a socket 4'7 formed on the outer surface of the head adjacent the socket 40.

A cam shaft 50, a portion of which is shown in Figure 3, supports a rotor 51 of molded insulating material. The rotor is driven by the cam shaft 50. This rotor comprises a main body portion 52 having arms 53 and 54. The arm 53 supports a metal strip 55 which projects to the center portion of the rotor and is adapted to be engaged by the spring pressed contact 44. The arm 54 supports a conductor 58 and the conductor is connected to a bushing 59 supporting an outwardly spring pressed brush or contact 60. The brush 60 is adapted to engage the circular track or conductor 37 connected to the high tension terminal 39. Eight of the posts 25 of the terminals 23 which have their ends 24 extending into the sockets 22 of the outer circle, extend from the ribs 32 and cooperate with the conductor arm 55, and in a like manner eight of the posts 25 of a series of terminals have their ends 24 extending into the sockets 21 of the inner circle which extend from the ribs 33 and cooperate with the conductor 58. Thus, each conductor 55 and 58 cooperates with a separate as I series of posts 25 and are so arranged with respect to each other that two sparking impulses will be conducted simultaneously to two spark gaps.

In the ignition system in which the disclosed distributor head is intended is illustrated diagrammatically in Figure 4. The operation of the system will now be set forth. When it is desired to operate an engine, not shown, the switch 64 is closed, permitting current to flow from the battery 65 to point 66; thence the current will flow through lead 67, primary winding 68 of an ignition coil '70, wire '71 to terminal 72, through leaf spring 73, contact arm 74 across the'contacts 75 and 76 and back to the battery through ground connections 77. From the point 66, current will also branch through wire 78, primary winding '79 of ignition coil 81, Wire'82, terminal 83, spring 84, arm 85, across contacts 86 and 87 and back to battery 65 through ground connections 8'7. It is to be understood, however, that in order to permit this flow of current the cam 88 is in such position that the. contacts 75, '76, and 86, 87 respectively, are closed. As soon as the cam 88 rotates to open the contacts, as illustrated in the diagrammatic showing, the sparking impulses will be induced inthe secondary windings 69 of the ignition coil .70 which will be directed through the wire 90 to the terminal 38, circular track 37, brush, contact strip and then to the terminal post 25 locatediin the bosses .33 associated with the inner circle of sockets 21 to receive the lead wire directed to the spark plugs of the engine. At the same time I sparking impulses will be induced in the secondary winding of the ignition coil 81, which will be directed through a Wire 91 to the termina143, spring pressed contacts. 44,. connecting strip, and thence to the various terminal posts 25 located in the. ribs 32 associated with theouter circle of sockets 22 adapted to receive a lead wire directed to another series of spark plugs of the engine.

From the foregoing description, it will'be understood that the distributor head constituting the subject matter of the invention is simple in its construction, yet will operate efficiently for the purpose described. The head may be used in connection with a sixteen cylinder engine having single spark ignition when the cylinders fire; When the head is to be used on a sixteen cylinder engine, the rotor 52 will have to be replaced by a rotor having corresponding segments 55 and 58, but the segments are so arranged that they will be diametrically opposite. At the same time, one of the circuit levers, for example, lever 85, would have to be shifted 22 from the position shown diagrammatically in Figure 4,

so that the rubbing blocks on the lever arms 74 and respectively, which cooperate with the cam 88, will open a circuit on every 22 of 'movement of the rotor to induce sparking impulses in the secondary windings 69 and 80 alternately and directed through their respective elements to a series of sprak plugs of the engine as has been described. "While the form of embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claim which follows.

- What is claimed is as follows: A unitary subassembly for an ignition device comprising; a distributor head of insulating material having a plurality of reinforced ribs, each rib having 'a flat portion, said ribs forming a corrugation and a step formation within said head, and said ribs being constructed and arranged so that each alternate rib forms a group lying in a plane spaced a substantial distance apart from the plane of the other group; and a terminal post molded within each of said ribs and extending beyond the flat portion of its respective rib, said terminals being substantially parallel to the axis of said head to form a plurality of circular rows of terminals having different diameters.

' CHARLES HALL DAVIS, JR. 

